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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 10 |
| 3 | 280 |
| 4 | 38080 |
| 5 | 18887680 |
| 6 | 39286374400 |
| 7 | 319319651123200 |
| 8 | 10504339243348787200 |
| 9 | 1374135642457914946355200 |
| 10 | 721146385161913763847208960000 |
| 11 | 1511615130036671973985522422906880000 |
| 12 | 12683442560532981918553467630898150113280000 |
| 13 | 425533759542581882449393472981756918078982062080000 |
[1,1,10,280,38080,18887680,39286374400, 319319651123200,10504339243348787200, 1374135642457914946355200, 721146385161913763847208960000, 1511615130036671973985522422906880000, 12683442560532981918553467630898150113280000, 42553375954258188244939347298175691807898206208000\ 0] |